The mistrial was the third time in a week that jurors weighing a fatal shooting by a police officer did not convict the officer involved, following acquittals in other cases. It was also the second time a jury has deadlocked considering this particular shooting.

Judge Leslie E. Ghiz, speaking from the bench, read from a note sent by the jurors who said they were “almost evenly split regarding our votes toward a final verdict” and unable to reach a unanimous decision.

The outcome came just days after officers were acquitted of deadly shootings in Minnesota and Wisconsin, and it concluded the second trial of Raymond Tensing, who was charged with murder after fatally shooting Samuel DuBose during a routine traffic stop in July 2015.

While Ghiz declared a mistrial, Tensing — seated at the defense table in front of her — initially stared straight ahead without responding, and then put his head down, rubbing his eyes with his left hand.

DuBose’s mother, Audrey, released a statement saying his family was “outraged that a second jury has now failed to convict Ray Tensing for the murder of our beloved Sam DuBose.” She also called for a third trial in the case.

A jury deadlocked in Tensing’s first trial in November, and Hamilton County prosecutor Joseph T. Deters quickly vowed to retry him, saying he hoped that another jury would “be able to reach a decision to bring justice in this case for the victim’s family and our community.”

Tensing, who was later fired by the university, stopped DuBose on the evening of July 19. According to the initial police report, Tensing had described being forced to shoot DuBose because he was being dragged by the car and nearly run over, which Deters said was untrue.

Like the cases in Wisconsin and Minnesota that recently ended with acquittals, DuBose’s death was captured on video. Footage from Tensing’s body camera, released the day he was arrested and charged, showed that the fatal encounter unfolded in less than two minutes.

DuBose, a 43-year-old unarmed man, was shot during a July 19 traffic stop in Cincinnati. As DuBose attempted to drive away, a University of Cincinnati police officer shot him in the head. The officer was later charged with murder and voluntary manslaughter. <i>The footage has been edited by WCPO to blur the victim's face.</i> (Hamilton County Prosecutors Office)

During the stop, Tensing asked DuBose, 43, to take off his seat belt, and DuBose is seen turning on the ignition. Tensing is then seen reaching toward the door, yelling “Stop!” and shoving his gun into the car window, firing a single round into DuBose’s head.

As the traffic stop began, Tensing greeted DuBose: “Hey, how’s it going, man?” The officer explained that DuBose was stopped for not displaying a front license plate on his green Honda Accord, and asked multiple times for DuBose’s license. DuBose eventually said he did not have it with him.

Tensing then asked DuBose to take off his seat belt. DuBose said he had not done anything wrong and appeared to turn the car back on, at which point Tensing drew his gun. After Tensing fired the fatal shot, the car lurched forward and eventually came to a stop down the street, while Tensing ran after it, shouting to a dispatcher that medical attention was needed.

Photos of Samuel DuBose at a memorial near where he was shot and killed. (Tom Uhlman/AP)

Announcing the charge against Tensing during a news conference 10 days later, Deters said that his office had reviewed more than 100 police shootings and “this is the first time that we’ve thought, ‘This is without question a murder.’ ”

An attorney for Tensing had dismissed the murder charge as “unwarranted” and said he felt charges were likely due to “the political climate here and nationally.” The attorney also said Tensing “was in fear of his life” when he opened fire.

After the second hung jury was announced Friday, Cincinnati city officials said they were disappointed with the decision but called on anyone who protests to do so peacefully.

“I, like so many others, share in the disappointment in the outcome from today’s jury,” Cincinnati Police Chief Eliot Isaac said at a news briefing.

DuBose was one of 991 people fatally shot by police officers in 2015, a number that was essentially unchanged last year, according to an ongoing Washington Post database tracking such shootings.

Police officers are rarely charged for fatal shootings or other uses of deadly force, and convictions are less common.

Since the beginning of 2005, 82 nonfederal law enforcement officers have been arrested after being accused of murder or manslaughter in connection with fatal on-duty shootings, said Philip M. Stinson, a criminologist at Bowling Green State University in Ohio, who studies arrests of officers and has kept data since that year.

From that count, 29 have been convicted of a crime, mostly on lesser offenses, Stinson said. More officers — 34 — were not convicted, largely due to acquittals. There are also 19 officers with cases still pending, according to Stinson, who counts Tensing among that number because prosecutors have not announced a decision on a possible third trial.

Five days earlier, former Minnesota police officer Jeronimo Yanez was acquitted of fatally shooting Philando Castile during a traffic stop last year that was partially streamed online. The aftermath of that shooting was broadcast on Facebook Live, drawing international attention.

Experts caution that even though video footage can be horrifying, such recordings may be incomplete, and noted that the legal standard still remains whether an officer’s actions were “objectively reasonable” at the time.

“Video may give us some insight on that, but it doesn’t change the fundamental standard by which police actions using force are judged,” said David A. Harris, a law professor at the University of Pittsburgh and an expert on police use of force. “Whether you think it’s right or wrong, that standard is favorable to the police. It tends to support their actions in the great run of cases.”

Harris also said that juries tend to come in giving officers “the benefit of the doubt” in most cases.

“Video is not a magic solution to this,” he said. “Sometimes, it will be very helpful. And sometimes it will put certain facts, even if not all the facts, but certain facts, beyond dispute. But many times, it does not put enough of the facts beyond dispute. … You add that to the favorable nature of the law and the fact that jurors tend to, as a group, start with sympathy for the police position, and what you have is a situation where it’s really tough for prosecutors to win those criminal cases.”

This story, first published at 2:28 p.m., has been updated with new information.